I have the opposite of a void (full white cat) who lived on the street till he was two. Not feral, since he was fed by someone, but by no means a tamed cat. I adopted him and haven’t seen the cat for three months he was hiding so much. Pheromones, visits to the vet to check if there’s something wrong (we had to take him out from under the couch with a training sword), nothing helped. He was also a trash panda, getting into everything and everywhere. Not able to be touched, running after any sound a slipper made.

What helped was a video with sound of a female kitty popping in and out of her carrier and meowing at the owner. I was absent mindedly watching cat videos and suddenly out the corner of my eye I see my cat for the very first time in months, outside the sofa. He got tame after 4 months or so after that, and progressively an outrageous cuddler. Sits on the lap, loves belly pets, etc. Just needed time to calm down. Still a great hunter though, you can’t run away with the mouse on a string / rod, he’ll always get you, always full-sending it, walls be damned. Had to shave out his paw pads with an ear trimmer, cause he slid so much I was scared he’ll hurt himself.